5
homey(adjective, cool, simple, relaxed, ordinary)
5
private(adjective, unauthorized)
5
slack(adjective, free, out, unrestricted, released)
5
sociable(open, easy, friendly, natural, bold)
5
unassuming(adjective, simple, ordinary, comfortable, unsophisticated)
5
unstudied(free, casual, impulsive, spontaneous, impromptu)
4
confabulatory(adjective, talkative)
4
cool(adjective, simple, informal, casual)
4
extemporaneous(adjective, free, casual, impulsive, spontaneous)
4
extempore(adjective, free, simple, casual, spontaneous)
4
frank(adjective, clear, open, simple, easy)
4
impromptu(adjective, free, casual, impulsive, spontaneous)
4
laid-back(adjective, cool, plain, informal, mild)
4
liberal(adjective, calm, clear, open, easy)
4
open(adjective, calm, clear, free, smooth)
4
outgoing(friendly, sociable, gregarious)
4
straightforward(adjective, simple, casual, succinct)
4
unauthorized(adjective, illegality)
4
unfussy(adjective, simple, casual)
4
unorthodox(unusual, strange, unique, eccentric, atypical)
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APASmart Define. (2016). informal thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/informal/thesaurus/synonyms
ChicagoSmart Define. 2016. "informal thesaurus" https://smartdefine.org/informal/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, informal thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/informal/thesaurus/synonyms>.
MLASmart Define. "informal thesaurus" 29 February 2016. Web. 25 September 2026. <https://smartdefine.org/informal/thesaurus/synonyms>